This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Changes in cancer therapy over the past 20 years have created better options for treatment and improvements in survival. Older adults over age 65 are a large and growing proportion of cancer patients and survivors, yet the functional cost of therapy in this vulnerable population is largely unknown. Potential changes include decreased strength, loss of lean body mass, decreased ability to perform tasks needed to participate in daily activities. Function declines will depend on function at baseline, the type of cancer and the side effects of the cancer therapy. Studies show that cancer patients who receive cancer treatment bear the burden of side effects from both cancer and treatment. Maintaining function is important to older adult's quality of life. In the future it will be increasingly important to help older cancer patients stay as functional as possible. The study looks at functional change of elderly cancer patients. Approximately 52 cancer patients age 65 or older will be asked to participate. Cancer patients asked to participate will be receiving cancer therapy with the intention of providing a cure. Functional change will be assessed from the time of diagnosis, through therapy to the early post therapy time frame. A comprehensive model explaining reasons for function change is used as the framework for choosing variables to measure. Components of function that will be measured include a 6 minute walk test, lower extremity muscle strength, a Short Physical Performance Battery assessing function of legs and a test that simulates typical household activities. Surveys will be used to subjects own assessment of their activity and function. The four most common cancer-related side effects will be measured and include fatigue, sleep impairment, shortness of breath and pain. Some markers in the blood may be abnormal and be related to declines in function. They will also be measured. Differences in function over time will be determined and relationships between function, cancer-related side effects and quality of life will be assessed. The proposed project will document the degree of function decline, assess the relationship between function and cancer- related symptoms and evaluate relationships between function and quality of life. A small amount of psychological distress may be associated with completing the questionnaires. The test to measure function may cause muscle fatigue or strain. Participants will meet safety criteria before their function is measured. Knowledge gained will help us plan interventions around the time of cancer therapy to help older adults preserve or improve function.